Multiple-unit single-control extension staging



Nov. 20, 1928. 1,692,664

- M. KIRSCH I 1 MULTIPLE uurr SINGLE cou'mop EXTENSION sueme W; Filed June 0. 1927 a Sheets-Sheet 1 'ATTORNEYY Nov. 20, l 928.

KIRSCH,

MULTIPLE UNIT SINGLE CONTROL EXTENSION STAGING 2 Sheets-Sheet 2 Filed June 30, 1927 ZBYVK VENTOR W Patented Nov. 20, 1928.

UNITEDVSTATES.

MICHAEL KIRSCH. or MILWAUKEE, WISCONSIN.

MULTIPLE-UNIT SINGLE-CONTROL EXTENSION STAGING.

Application filedlune 30, 1927. Serial N0. 202,662.

My invention relatesto multiple unit extension staging.

The objects of my invention are to provide a series of supporting units for staging adapted to be individually or collectively ad justed in height from a single manualcontrol. More particularly stated, the object of my invention is'to provide aseries of like extensible staging units each providedwith a mechanismfor individually adjusting the particular staging'unit and provided with communicating motion transmitting connectio'nsfor simultaneous adjustment of the entire series. Y I In the drawings:

Figure 1 is a fragmental front elevation showing'two units of a series of staging supports equipped with my invention.

' Figure 2 is a side view of one of my staging units showing my drum and cable'mecha nism for intercontrol of mystaging units.

Figure 3 is adetail plan view of the drum andclutch mechanism andslide'in each of my staging units. 5

Figure dis a section on line 44 of Figure 3.

" Figure'5 is a detail of a pa'rt'of the throwout mechanism for my d-rum control.

Like parts are identified by the same reference characters throughout the several views.

Each of my staging units comprises fun d amentall y the well-known form of extension ladder consisting of af'main ladder '1 and its extension 2 slidably'mounted upon one another. A bar?) comprisesa retaining member and, the clamp 4 secured at either end thereof forms a pivotal connection at 5 for adjustable braces 6 which extend as shown in Figure 1 from the top of one ladder to the bottom of another ladder comprising the n ext unit of the series control which is the essence of my invention." The extension 2 of each unitof the series may be used to support the usual staging planks 7 upon the bracket 8 secured to'rungs 9 of the extension.

A pulley 1O mountedupon the bar 3 ceives the cablell which'is adapted to raise and lower the extension under the control of the drum and clutch mechanism now t be described. u

At a convenient'height' for manual operation is provided a frame work 20 near the base of each of the main ladders 1; lVithin this frame work and mounted in a horizontal position at right angles to the rungs 9 of the ladders is a pair of drums and 26 upon,

shaft 27 rotatable in bearings 21 and 22, the drum 25 being splined' to the shaft 27 and drum 26 being-mounted for free rotation thereon. Drum 25 is mounted on the shaft 27*for limited reciprocation axially of the shaft to the end thatthe drum 25 may be moved'rearwardlyin the direction of drum 26 and cause dogs 28 and 29 which are in tegral with drums 25 and 26 respectively to engage one another, with the result that re tation of the shaft 27 and the drums 25 will alternatively turn the drum 26 or leave it free for rotation on shaft 27 accordingly as the drum 25 is moved rearwardly or forwardly at the will of the operator; Collars 30 secured tightly to shaft 27 by means of set screws 31, or otherwise, limit the forward or rearward movement of the shaft 27 as indfcated in Figure 3. The lever'32 may' ibe pivotally positioned upon itsmount-ing 33 to provide manual control of the drum 25. A rack 35 and pawl 36 construction is provided as shown in F ig.'3 to prevent motion of the drum 26 at times when the clutch dogs 28 u and 29 are in disengaged position- -Motion transmitting links 37 and 38 may be rovi'ded to immediately engage the pa-W 36 with the rack 35 automatically when the drum-25 is disengaged from the drum 26. A crank 34 is provided for manual rotation: of theshaft2. For operation of-aseries of staging units each of which is provided with the drum mechanism above described I have provided for the winding of cable 11 upon drum 25 a number of times around each of the drums '26 successively throughout the series of stagand I have provided a cable 40 to be wound trolled by' these'cableswill thereafter'be as follows. "When the units of my staging system are finally placed imposition in connection with a building wall such as that shown at 45 any regularities in the ground or supporting material at 50 may be compensated for by individual adjustment of each staging-unit extension 2 by throwing the lever 32 backward thereby releasing the clutch dogs 28 and 29 from" engagement with one another. Rotation of the shaft 27 by means of the crank 34 will then cause the cable 11 to be drawn in upon the. drum 25 or released from ordinating the rotation of the auxiliary and main drums of each base section and a crank connected with each main drum for manual rotation thereof.

7. A multiple unit staging, including a plurality of extensible units provided with base sections and extensible sections, a frame for each base section, a main shaft for each frame, a main drum mounted upon said shaft for rotation therewith, an auxiliary drum mounted for rotation upon said shaft, clutch dogs for each of said drums adapted to interlock to cause simultaneous rotation of the drums, a clutch arm for slidably moving one of said drums to cause said clutch dogs to interlock, a ratchet and pawl for controlling rotation of the auxiliary drum, a link between one of the drums and the pawl, whereby to cause the pawl to be disengaged from the ratchet when the clutch dogs are interlocked, cable connection between the auxiliary drums Wherebyto cause said drums to be simultaneously rotated and cable connection between the main drum and the extensible unit associated therewith. MIKE KIRSCH. 

